Traction sheave



Dec. 20, 1927,

E. L. RIESKE TRACTION SHEAVE Filed MarchlS, 1925 Patented Dec. 20, 1927.

nnwAnnL. nIEsKn, or DAYTON, onto.

memoi senate. 1

a lication:fiieaiviareh'is, 1925. j seiin No. 16,481.

My invention relates to pulleys and more particularly to traction or power sheaves uniform in'operation, automatically controljled and'unlikely to getout of repair.

for hoisting apparatus, felevators and the like.

is to provide hoisting or elevator sheaves with V grooves, of approximately thlrtythree degrees divergence in which the hoist cable engages with a wedging effect. The entrance of the cable intosuch convergent groove, and its disengagement therefrom is by a lateral wiping action,which not only i creates wear uponvthe cable, but also wears the sides of the grooves until after comparatively short periods of use such grooves,

wear into substantial conformity with the .cross sectional contour of the cable.

cable then no longer engages tightly within such grooves, but the cable and pulley possess thetendency to slip idly one relative to the-other. The present invention is designed to overcome this ,difliculty by providing relatively movable shoes or ring linings within enlarged grooves in the face ofthe.

pulley or sheave, which shoes or lining rings when subjected to. the pull of the cable on the bottoiu'of its seat tend to. contract illwardly to clamp the cable laterally between the shoes or ring linings of the groove. 'Th'is contractive mo vement of the shoes nto gripping or clamping engagement w th the cable is increased and supplementedi by thewedg ing action of rollers wh chexterlorly ens gage the shoes .or .groove'hmngs andserve to press such, shoes or, linings (laterally against the, cable. 1 This pressure of the shoes under the influence of the wedge roll ers is controlled the tension of thecable, thru an idler roller riding up'onthe cable and-carriedfby abell crank lever, which also carries the wedge rollers So long asthe cable is under tension," its reaction against the idler roller will press the V shaped wedge rollers into engagement with the cable gripping shoes or groove lin ngs. However, if,

thelelevator car overruns, or the cable is otherwise slackened, such relaiiation of the cable tension permits a relaxation of the wedging pressure of the rollers upon the cable gripping shoes to simultaneously release the cable so that it may be free tocoine and go independent of thesheave.

' The object of the invention is to simplify;

the construction'as well as the. means and mode of operationfof gripper type pulleys or traction sheaves, whereby they will not The common practice'at the present/time I provide-an improved form of cable gripping The " provide a tension operated governor, by l which the clamping action of the "cable grip- 5 V ping deviceswillbe increased as the tension only'b'e cheapene'din construction, but will be more eflicientin use," positive in action,

A further object of the invention is to gripping pressure being gradually applied until apoint of maximum clamping engagement is reached at the top of the pulley or sheave, whereupon such'engagement of the cable is gradually relaxed, until the cable is permitted to leave such gripping devices freely andwith'minimum friction or wear. A further object of the invention is to or pullupon the cable increases, and which conversely will relax and release the. cable when slack occurs therein, permitting the. cable to pass idly over the sheave or, pulley,

to compensatefor rebound or overrun.

A further object of the invention is to provide an improved form of replaceable interlinings for the. 'groove sfiof pulleys orsheaves, so constructed and'zarranged as to 8 minimize wear thereon," but capable of ready a interchange and replacementif worn after long periods of. use. 4

WVith the] abOVeQprimaryand other incidental objects in vieWas willmore fully ap .pearin the specification, the invention consists of the features of construction, the

parts and combinations thereof, and the mode .of operation or their equivalents as hereinafter described and set forth in the claims,

In the accompanying drawin gs,wherein 1s shown the preferred, but obviously not f necessarily the only form of embodiment of,

the invention, Fig. 1 isa transverse sectional View of l the transverse powersheave or pulley, in which the present invention is embodi ed. Fig. 2 is a side elevation thereof;

'Fig.' 3 isa sectional perspective view of. one i of the cable shoes orrlms linlng the grooves removed from the pulley. I r I Likeparts are indicated by similar characters of reference throughout the several views. I

Referring to the accompanying drawings,

be of any suitable' or desirable construction 110 1 indicates ,jthe sheave or pulley, which may.

' face of the groove by "an external head or rib 7, which bears against the interior face of tions 22,' removably secured to the .main

or size, having" lateral detachable rim secpulley body 1, by transverse clamp bolts 3.

The face of the pulley is provided with parallel grooves, each formed partially in the main body and'partially in' the removable rim sections 2. While for convenience of illustration, the invention has been' shown in the drawings as embodied in a pulley or sheave having but two grooves, it will be un-;

1 derstood that the construction is applicable c of somewhat greater radius than'thatof the cable 5, so that the cablemay freely enterand leave the shoes or rings within the groove, without frictional or wiping action.

Theshoes or lining rings 6 are supported in.

slightly spaced relation with the interior the groove 4 in the pulley serving as a spacer forthe shoe or lining ring 6,,and also performing the functions of a fulcrum, upon which the shoe vor lining ring. is capable of a transverse tilting or warping movement.

The annular shoes or lining rings 6 are preferably, though not necessarily,-slightly greater in diameter than the grooves in which they are to fit, so that when the rings are seated in the grooves-at the top of the pulley or sheave, there will be a slight clearancediametrically at the. bottom of the sheave. This clearance in any event would be quite small for example, approximately one eighth of an inch on a twenty-four inch pulley. ,However, this diametrical clearmice is not an essential. The shoes or lining rings 6 are interengaged with the pulley byfkeying or interlocking in any suitable manner to preventindependent rotation or circumferential slippage u on the pulley.

' A simple but efiicient met od of interengaging-the shoes orv lining ring with the pulley against relative circumferential movement .while permitting freedom for rocking or warping movement of the ring is afforded byproviding studs or pins 8, 7, g

' cable may be effectedfby a distortion or seated in the interior face of the pulley groove and loosely engaging corresponding sockets or shallow holes 9 in the exterior faces of the shoes or lining rings 6. Nor

or lining ring sections 6. When, however,

the cable is subjected to pulling or tension, causing it to bear more heavily upon its seat upon such shoes or ring 6, the rings will be distorted or warped into a tilting action about their bearing point upon the head or rib 7. As the pressure or tension of the cable deflects the adjacent margins. of the shoes or rings 6, at the bottom of the groove 41. inwardly toward the center of the pulley, this tilting or warping action will be transmittedto the outstanding sides of therings or shoes 6 which will be deflected inwardly into gripping or clamping pressure laterally upon the cable 5. This clamping or gripping effect will be greater at the point opposite the direction of pull.

of the cable, or at the top of the pulley in the case of an elevator sheave. From this point of greatest pressure of the cable upon the shoes or rings 6, that is to say, the medial point of contact between the cable and the sheave, the gripping or clamping effect of the rings upon the cable will be progressively less in either direction. 'At the pointwhere the cable first engages with the sheave and also at the point where'the cable leaves the sheave there will be no clamping or gripping effect. From these points, however, toward the point of greatest pull or pressure of the cable upon the sheave, a I

gradual ncrease of gripping or clamping pressure is effected. Thus the cable enters the sheave groove, easilyand'freely. As it progresses around theshe'ave, the shocsor lining rings ofthe groove gradually contract transversely of the groove and cable, as the.

pressure upon such shoes or rings at the bot-v tom of the groove; increases, until at the medial point of greatest pressure, when the :cable is firmly gripped. This grippingao tion is proportionate to the-pull or tension.

of the cable- As the tension or pull upon the cable increases, the gripping or clampy ing action of the shoes or rlngs will also proportionately increase to resist any slip-' page of the cable, and as the tension upon the cable'relaxes, the shoes or rings 6 also relax their vengagement. As the cable passes the point of greatest pull or pressure, the

gripping action. of the shoes or rings 15 graduallvrelaxed until finally the cable is entirely free to leave the sheave or pulley without frictional resistance or wiping action and without the necessity of'tearing itself from its engagement withinthe groove This gripping or clamping action of the warping of the'rings or shoes 6, constituting in effect a tilting or fulcrum movement of the engaged portion of the ring upon its as is the case when the cable'is wedged in p V shaped grooves as commonly employed.

I paratively pressed by the pull of the cable, toward the bottom of thegrooved. pulley, at the 3 same tlme tilting the outer margin of the ringershoe inward against the side of the cable.

This warping or distortion of the'rings or shoes will be progressive circumferentially of such ring as the pulley or sheave rotates. In the event that the rings. or shoes arecomloosely mounted: .-in pulley grooves' tby the provision of the clearance before mentioned, and by making the socket diametrically opposite point. 1 By mounting the ring sufficiently loose Withinthe groove 4, yet so interconnected with the pulley as to prevent relative rotation,:the clamping eiiect of the cable may be achievedfwithout the necessity of warpingor distorting the rings.

To the contrary, by making the rings of material having suflicient degree of flexibility, the gripping or clamping action may be effected solely by the distortion or warp ing of the rings independent of any displacement or side play at ajdi-ametrically opposite point.

to employ the distortion or warping of'the ring and the lateral displacement 1 at the; opposite side of the pulley, both to limited degrees in conjunction with each other. I As a further: means of insuring operative;

clamping engagement of the shoes or rings] with the cable, the outer faces of the pe;

ripheral margins of the rings or shoes 6- are inclined or beveled at 10 for; engagement therewith of a'series of V'shaped pressure; or wedge rollers 11. 2 These rollers .ll ar'el located contiguous to the point'of greatest pull or pressure of the cable upon the sheave and consequently the point ofv greatest clamping or gripping engagement of the, shoes or rings'G with the cable. 7 The wedgej shaped peripheries of the pressure roller 11, engage between the beveled margins of the shoes or rings 6 and the marginal side wall of the pulley groove 4, or in the event that the grooves 4: and shoes or ringscontained therein are closely located, such pressure rollers 11 might simultaneously engage two of the clamp shoes or ring 6, by pro- Jecting intermediate beveled or inclined faces 11, as indicated at 12 uponithefdraw ing. By their inward radial pressure toward the axis of rotation-of the pulleyor sheave, such wedge rollers 11 .eXer-t lateral camming pressure uponthe shoes or rings 6 tending to tilt or warp the standing sides or outer margins of the rlngs or shoes laterally against the sides ofthe cable'.5.,

Obviously, the greater the depth to which It is preferred, however, to adopt an intermediate plan'of operation and.

such V shaped or wedge rollers 11 'arethrust i 1 into engagement-with the bevel margins of tlieshoes or rings 6, the-tighter will be the gripping effect of such-shoes or rings upon a 1 :drawing the wedgerollers from engagement the interposed cable 5. Likewise, by? withwith the shoes, the tension upon the shoes is relaxed and the cable proportionately released. To control this thrust engagement of the wedge rollers. 11 with the shoes or rings'6, suchrollers are mounted upon a bell crank leverl3, pivoted at 14, and carrying on the opposite arm of such lever a governor Wheel or idler '15, which engages the run of the'cable 5. The pivotal point 14: ofsthe bell crank lever is preferably 10- catedlinwardly toward the pulley and to ward the wedge rollers 11 from the plane in which the governorroller 15 normally operates. Thus the tendency .will be for'the bell crank lever 13 to oscillate about its pivot-alconnectionunder influence of gravity to lift the wedge "roller out of engagement with the shoes or ringswhenever the cable 5 permits such inward swinging move-y ment of the governor rollers 15. i If desired,

this releasing movement of theflbell crank leverinay be-assisted by a spring 16, So long as the cable 5 isunder strainer tension it tends to push the governor roller 15outw'ardly, thereby. oscillating. the'bell crank lever about its pivotal connection to press tliewve'clge rollers 11, firmly into engagement with the severalz'margins ,ofthe shoes or rings6. 'However, in the event thatthe cable overruns or the load is taken off the cable, so that the tension of-the cable relaxedbor slack therein accumulated, the

cable no longer exerts its outward pressure upon. the governor roller 15, but allows the bell crank lever to swing about the pivotal connection, either underinfluence ofgraw, 'ity, or the spring 16, thereby lifting the wedge rollers 11, and'permittingthe shoes or rings 6 to relaxtheir clamping or grip plng-engagementnpon thecable 5, whereupon the cable is free to come or go within the pulley grove. ,The governing action of thew edge rollers 11is thus'automatic. As

the cable tension increases, the pressure of thewedge rollers 11 is automatically increased to proportionately increase the gripping action of the shoes or rings upon the r the cableis relaxed, the engagement of the vwedge rollers with the shoes "or rings is proportionately relaxed. It will be seen that by this means,the traction engagement of the cable with the pulley is directly pro-' v portionate at all times to the work to be performed.

7 From theabove description it will-be .cablen To the contrary, as the tension of parent thatthere is thus provided a device of the characterdescribed possessing the r particular features. of advantage before enumerated as desirable, but which obviously is susceptible of modification in its form, proportions, detail construction and arrangement of parts without departing from the principle involved or sacrificing.

any of its advantages. L

VVhilein order to comply withthe statute the invention has been described in language more or less specific as tostructural f-ea-' tures, it is to be understood that the invention is not limited to the speciflodetails shown, but that the means and construction herein disclosed comprise the preferred form of several modes of putting the inven tion into effect and the invention is, there fore, claime'd'in any of its forms or modifications within the legitimate and valid scgpe of the appendedclaimsq 1 aving thus described my invention, I claim: V

1. The combination with a pulley of cable gripping means carried thereby, wedging means controlling the gripping means and means for automatically adjusting said wedging means to vary their pressure, and

thereby regulate the gripping means in accordance with the tension of the cable.

2. The combination with a pulley having expansible and contractiblecable grooves in the periphery thereof, and a variable cable guide engaging the cable ata point removed from the pulley and governed by the tension 7 of a cable passing thru the groove and means for contracting such groove to grip the cable operated by the variations of the cable guide. 3. The combination'with a pulley of cable gripping means carried thereby, of govern- 1ng means having operative. engagement with the cable at a point removed' from the. pulley engaging the. cable grippingmeans for contractmg the latter upon the cable,

and automatically controllingthe pressure thereof by the tension of the cable;

4. The combination with a pulley and transversely cable gripping devices carried thereby, of wedging meansbearing upon and tending to contract the cable gripping devices with yielding pressure and 'means' for controlling the yielding pressure of the rollers by Variations of the cable tension.

5. The combination with a cable pulley, 0t means for regulating the operative driving engagement thereof, including a wedging means and. means controlling the wedgingmeans by fluctuations of cable tension,

to insure operative driving engagement between the pulley and a cable. 1 Y

r 6. The combination with a cable'pulley of cable gripping devices carried thereby, cam members operating to elfect engagement of the; gripping devices with the cable anda control lever having operative engagement with the cable at a point removed from the pulley for controlling the cam'membersby the variations of the cable tension.

'7. The combination with a cable pulley I having-a peripheral groove, of a circumfer:

entially split lining for such groove :inter engaged therein against independent circum ferential movement relative to the pulley, the sections of, which are circumferentially continuous and capable of transverse rocking movement toward and from each other under influence of cable tension into and out of gripping engagement with the cable.-

8. The combination with a cable pulley having a peripheral groove, of a pair of continuous flexible but non-compressible clamp rings located within the groove, said rings pressure in which the cable seating portion of the rings is depressed within'the pulley, groove and the lateral portions of the rings tilted inwardly into lateral clamping engagement withthe cable.

10. The combination'with a cable pulley having a peripheral groove of a pair of con cave non-compressible rings mounted within the groove in spaced relation with the interior walls thereof and forming a seat for the cable, said rings being capable of a warp ,ing movement' under the influence of the cable pressure by which the sides of the concave'rings are deflected into lateral engagement with the sides of the cable.

11. The combination with a cable pulley having a peripheral groove,and a continuous 1 flexible but non-compressible lining for said groove capable of warping movement under the influence of the cable pressure thereon, the lining being progressively contractible and; expansible in proportion to the cable pressure exerted thereon to vary its engagement, with the cable;

12. The combination'with a cable pulley having a peripheral groove and a continuous expansible and contractible but non-compressible lining for the groove controlled by the influence of the cable pressure thereon to vary the operative driving engagement of the cable and groove lining.

having a peripheral groove, a pair of oppoin the groove, said rings having exterior bearing projections engaging the interior walls of the groove to support the rings in spaced relation "therewith, said rings formsitelydisposed concave rings mounted withing ayielding seat fora cable operatively gripped by the rings. upon yielding movement thereof. I I 4 14. The combination witha cable pulley 13. The combination-with a cable pulle 1 having a peripheral groove, a pair of oppositely disposed concave rings mounted within the groove, means for interengaging the rings with the pulley against relative circumferential movement, but permitting relative lateral tilting movement thereof into and out of clamping engagement with a cable seated thereon.

15. The combination with a cable pulley having a peripheral groove, a pair of oppositely disposed concave rings mounted within the groove, 2. series of spaced studs interconnecting the rings and pulley for unison rotation while permitting relative lateral deflecting movement thereof into and out of clamping engagement with a cable seated thereon.

16. The combination with a cable pulley, of cable gripping means carried thereby and a cable engaging therein, of a pressure means for increasing the operative driving engagement of the cable "and pulley, and neans for automatically varying the pres sure means by the deflection of the cable under varying tension strains.

17. The combination with a cable pulley,

of. cable gripping means carried thereby and a cable engaging therein, of a roller for increasing the operative driving engagement of the cable and pulley, a lever upon which the roller is carried and means for oscillating the lever in. accordance with fluctuations of cable tension. l

18. The combination with a cable pulley, of cable gripping means carried thereby and a cable engaging therein of a roller for increasing the operative driving engagement or" the cable and pulley, a lever upon which the roller is carried, and a second roller carried bythe lever in s aced relation with the pulley, whereby uctuations in the cable tension will effect the oscillation 0t the lever to vary the operative driving engagement of the cable and pulley. j

19. The combination with a cable pulley, of cable gripping means carried thereby,

a roller operatively engaging the cable grip Y Y ping means to efl'ect its engagement with the cable, and a control lever for said roller having operative engagement with the cable in spaced relation with the pulley and operating to vary the engagement of the roller in accordance with fluctuations of the cable tension.

20. The combinationwith a cable pulley of cable gripping means carried thereby,

a wedge roller engaging with the cable gripping means'and exerting cammlng pressure thereon to effect operative driving en-' gagement between the gripping means and cable.

21. The combination with a cable pulley having a peripheral groove, of an expansible and contractible lining for the groove,

of the cable tension for adjusting the cable sheave and cable. 7

a wedge roller engaging intermediate the lining and side of the groove as the pulley rotates serving by its camming action to contract the lining upon acable within such lined groove. v 1

- 22. The combination with a cable pulley havinga peripheral groove, of a movable cable clamp ring mounted therein, and a roller operating against said clamp ring'to move said ring into clamping engagement with the cable.

23. The combination with a cable pulley having a peripheral groove, of a movable cable clamp ring mounted therein, means operating against said clamp ring to move said ring into clamping engagement with the cable, and means for regulating the andkoperat ing means theretorhavingengagement with the cable atv a point removed from the pulley and governed by variation gripping means. i

v 25. The combination with a traction sheave for a cable, of an adjustablymounted idler pulley engaging the cable at a point removed from the sheave and automatically adjustable in accordance with variations of cable tension,'and means governed by the adjustment of said idler pulley for varying the traction engagement of the 26. The combination with a traction sheave for a cable of a cable guide tending to deflect the cable out of a straight line i against the tension of said cable, and means governed by the deflection of the cable from a straight line for varying the traction engagement of the sheave. Y

27. The combination with a cable pulley of cable gripping means carried thereby, a cable guide tending to deflect the cable out of a straight course against the pulling tension of the cable and an operative 'conmotion between 1 the cable guide and the cable gripping means by which the de ree of gripping engagement is governed by 110- tuations of the cable tension. 28. The combination with a traction sheave for a cable, of an adjustable cable guide tending to deflect the run of the cable out of a straight line and variable under influence of fluctuations of cable tension, and means for varying the. traction engagement of the sheave and cable by the adjustment.

of said cable guide. p

In testimony whereof, I have hereunto set my hand this 9th day of March A. D. 1925. y

EDWARD L. RIESKE. 

